2009 135i drivers window malfunction

[Jeff J]

2009 135i coupe 6MT Msport, 75k miles. Got in the car this morning and started it, then closed the drivers door. The window opened all the way on its own (in a controlled way - it did not freefall), and will not come back up. When I try the "up" switch, I hear electrical things, plus something mechanical that is definitely not normal. but the window does not move. Similarly if I push the "down" button, I get the same kinds of noises but no motion.

Suggestions on cause and potential fixes?

[b1aze]

If the regulator fails it likely won’t cause the window to free-fall as it still has to wind the motor backwards. I’ve never had it happen personally though so this is purely speculation.

[Jeff J]

Forgot to update this thread with the outcome.

As expected, the cable of the driver's window regulator failed. I was able to complete the replacement myself with the help of a C-spanner wrench from a 1984 Honda 3-wheeler (!) loaned from a friend. It perfectly fit the big sprocket head fasteners that clamp the window glass, and made short work of the job. It even feels like there's less wind noise around the glass now that I've done some adjustments.